1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/media/libvpx/vp8/encoder/encodemv.c Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,380 @@
1.4 +/*
1.5 + * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
1.6 + *
1.7 + * Use of this source code is governed by a BSD-style license
1.8 + * that can be found in the LICENSE file in the root of the source
1.9 + * tree. An additional intellectual property rights grant can be found
1.10 + * in the file PATENTS. All contributing project authors may
1.11 + * be found in the AUTHORS file in the root of the source tree.
1.12 + */
1.13 +
1.14 +
1.15 +#include "vp8/common/common.h"
1.16 +#include "encodemv.h"
1.17 +#include "vp8/common/entropymode.h"
1.18 +#include "vp8/common/systemdependent.h"
1.19 +
1.20 +#include <math.h>
1.21 +
1.22 +#ifdef VP8_ENTROPY_STATS
1.23 +extern unsigned int active_section;
1.24 +#endif
1.25 +
1.26 +static void encode_mvcomponent(
1.27 + vp8_writer *const w,
1.28 + const int v,
1.29 + const struct mv_context *mvc
1.30 +)
1.31 +{
1.32 + const vp8_prob *p = mvc->prob;
1.33 + const int x = v < 0 ? -v : v;
1.34 +
1.35 + if (x < mvnum_short) /* Small */
1.36 + {
1.37 + vp8_write(w, 0, p [mvpis_short]);
1.38 + vp8_treed_write(w, vp8_small_mvtree, p + MVPshort, x, 3);
1.39 +
1.40 + if (!x)
1.41 + return; /* no sign bit */
1.42 + }
1.43 + else /* Large */
1.44 + {
1.45 + int i = 0;
1.46 +
1.47 + vp8_write(w, 1, p [mvpis_short]);
1.48 +
1.49 + do
1.50 + vp8_write(w, (x >> i) & 1, p [MVPbits + i]);
1.51 +
1.52 + while (++i < 3);
1.53 +
1.54 + i = mvlong_width - 1; /* Skip bit 3, which is sometimes implicit */
1.55 +
1.56 + do
1.57 + vp8_write(w, (x >> i) & 1, p [MVPbits + i]);
1.58 +
1.59 + while (--i > 3);
1.60 +
1.61 + if (x & 0xFFF0)
1.62 + vp8_write(w, (x >> 3) & 1, p [MVPbits + 3]);
1.63 + }
1.64 +
1.65 + vp8_write(w, v < 0, p [MVPsign]);
1.66 +}
1.67 +#if 0
1.68 +static int max_mv_r = 0;
1.69 +static int max_mv_c = 0;
1.70 +#endif
1.71 +void vp8_encode_motion_vector(vp8_writer *w, const MV *mv, const MV_CONTEXT *mvc)
1.72 +{
1.73 +
1.74 +#if 0
1.75 + {
1.76 + if (abs(mv->row >> 1) > max_mv_r)
1.77 + {
1.78 + FILE *f = fopen("maxmv.stt", "a");
1.79 + max_mv_r = abs(mv->row >> 1);
1.80 + fprintf(f, "New Mv Row Max %6d\n", (mv->row >> 1));
1.81 +
1.82 + if ((abs(mv->row) / 2) != max_mv_r)
1.83 + fprintf(f, "MV Row conversion error %6d\n", abs(mv->row) / 2);
1.84 +
1.85 + fclose(f);
1.86 + }
1.87 +
1.88 + if (abs(mv->col >> 1) > max_mv_c)
1.89 + {
1.90 + FILE *f = fopen("maxmv.stt", "a");
1.91 + fprintf(f, "New Mv Col Max %6d\n", (mv->col >> 1));
1.92 + max_mv_c = abs(mv->col >> 1);
1.93 + fclose(f);
1.94 + }
1.95 + }
1.96 +#endif
1.97 +
1.98 + encode_mvcomponent(w, mv->row >> 1, &mvc[0]);
1.99 + encode_mvcomponent(w, mv->col >> 1, &mvc[1]);
1.100 +}
1.101 +
1.102 +
1.103 +static unsigned int cost_mvcomponent(const int v, const struct mv_context *mvc)
1.104 +{
1.105 + const vp8_prob *p = mvc->prob;
1.106 + const int x = v;
1.107 + unsigned int cost;
1.108 +
1.109 + if (x < mvnum_short)
1.110 + {
1.111 + cost = vp8_cost_zero(p [mvpis_short])
1.112 + + vp8_treed_cost(vp8_small_mvtree, p + MVPshort, x, 3);
1.113 +
1.114 + if (!x)
1.115 + return cost;
1.116 + }
1.117 + else
1.118 + {
1.119 + int i = 0;
1.120 + cost = vp8_cost_one(p [mvpis_short]);
1.121 +
1.122 + do
1.123 + cost += vp8_cost_bit(p [MVPbits + i], (x >> i) & 1);
1.124 +
1.125 + while (++i < 3);
1.126 +
1.127 + i = mvlong_width - 1; /* Skip bit 3, which is sometimes implicit */
1.128 +
1.129 + do
1.130 + cost += vp8_cost_bit(p [MVPbits + i], (x >> i) & 1);
1.131 +
1.132 + while (--i > 3);
1.133 +
1.134 + if (x & 0xFFF0)
1.135 + cost += vp8_cost_bit(p [MVPbits + 3], (x >> 3) & 1);
1.136 + }
1.137 +
1.138 + return cost; /* + vp8_cost_bit( p [MVPsign], v < 0); */
1.139 +}
1.140 +
1.141 +void vp8_build_component_cost_table(int *mvcost[2], const MV_CONTEXT *mvc, int mvc_flag[2])
1.142 +{
1.143 + int i = 1;
1.144 + unsigned int cost0 = 0;
1.145 + unsigned int cost1 = 0;
1.146 +
1.147 + vp8_clear_system_state();
1.148 +
1.149 + i = 1;
1.150 +
1.151 + if (mvc_flag[0])
1.152 + {
1.153 + mvcost [0] [0] = cost_mvcomponent(0, &mvc[0]);
1.154 +
1.155 + do
1.156 + {
1.157 + cost0 = cost_mvcomponent(i, &mvc[0]);
1.158 +
1.159 + mvcost [0] [i] = cost0 + vp8_cost_zero(mvc[0].prob[MVPsign]);
1.160 + mvcost [0] [-i] = cost0 + vp8_cost_one(mvc[0].prob[MVPsign]);
1.161 + }
1.162 + while (++i <= mv_max);
1.163 + }
1.164 +
1.165 + i = 1;
1.166 +
1.167 + if (mvc_flag[1])
1.168 + {
1.169 + mvcost [1] [0] = cost_mvcomponent(0, &mvc[1]);
1.170 +
1.171 + do
1.172 + {
1.173 + cost1 = cost_mvcomponent(i, &mvc[1]);
1.174 +
1.175 + mvcost [1] [i] = cost1 + vp8_cost_zero(mvc[1].prob[MVPsign]);
1.176 + mvcost [1] [-i] = cost1 + vp8_cost_one(mvc[1].prob[MVPsign]);
1.177 + }
1.178 + while (++i <= mv_max);
1.179 + }
1.180 +}
1.181 +
1.182 +
1.183 +/* Motion vector probability table update depends on benefit.
1.184 + * Small correction allows for the fact that an update to an MV probability
1.185 + * may have benefit in subsequent frames as well as the current one.
1.186 + */
1.187 +#define MV_PROB_UPDATE_CORRECTION -1
1.188 +
1.189 +
1.190 +static void calc_prob(vp8_prob *p, const unsigned int ct[2])
1.191 +{
1.192 + const unsigned int tot = ct[0] + ct[1];
1.193 +
1.194 + if (tot)
1.195 + {
1.196 + const vp8_prob x = ((ct[0] * 255) / tot) & -2;
1.197 + *p = x ? x : 1;
1.198 + }
1.199 +}
1.200 +
1.201 +static void update(
1.202 + vp8_writer *const w,
1.203 + const unsigned int ct[2],
1.204 + vp8_prob *const cur_p,
1.205 + const vp8_prob new_p,
1.206 + const vp8_prob update_p,
1.207 + int *updated
1.208 +)
1.209 +{
1.210 + const int cur_b = vp8_cost_branch(ct, *cur_p);
1.211 + const int new_b = vp8_cost_branch(ct, new_p);
1.212 + const int cost = 7 + MV_PROB_UPDATE_CORRECTION + ((vp8_cost_one(update_p) - vp8_cost_zero(update_p) + 128) >> 8);
1.213 +
1.214 + if (cur_b - new_b > cost)
1.215 + {
1.216 + *cur_p = new_p;
1.217 + vp8_write(w, 1, update_p);
1.218 + vp8_write_literal(w, new_p >> 1, 7);
1.219 + *updated = 1;
1.220 +
1.221 + }
1.222 + else
1.223 + vp8_write(w, 0, update_p);
1.224 +}
1.225 +
1.226 +static void write_component_probs(
1.227 + vp8_writer *const w,
1.228 + struct mv_context *cur_mvc,
1.229 + const struct mv_context *default_mvc_,
1.230 + const struct mv_context *update_mvc,
1.231 + const unsigned int events [MVvals],
1.232 + unsigned int rc,
1.233 + int *updated
1.234 +)
1.235 +{
1.236 + vp8_prob *Pcur = cur_mvc->prob;
1.237 + const vp8_prob *default_mvc = default_mvc_->prob;
1.238 + const vp8_prob *Pupdate = update_mvc->prob;
1.239 + unsigned int is_short_ct[2], sign_ct[2];
1.240 +
1.241 + unsigned int bit_ct [mvlong_width] [2];
1.242 +
1.243 + unsigned int short_ct [mvnum_short];
1.244 + unsigned int short_bct [mvnum_short-1] [2];
1.245 +
1.246 + vp8_prob Pnew [MVPcount];
1.247 +
1.248 + (void) rc;
1.249 + vp8_copy_array(Pnew, default_mvc, MVPcount);
1.250 +
1.251 + vp8_zero(is_short_ct)
1.252 + vp8_zero(sign_ct)
1.253 + vp8_zero(bit_ct)
1.254 + vp8_zero(short_ct)
1.255 + vp8_zero(short_bct)
1.256 +
1.257 +
1.258 + /* j=0 */
1.259 + {
1.260 + const int c = events [mv_max];
1.261 +
1.262 + is_short_ct [0] += c; /* Short vector */
1.263 + short_ct [0] += c; /* Magnitude distribution */
1.264 + }
1.265 +
1.266 + /* j: 1 ~ mv_max (1023) */
1.267 + {
1.268 + int j = 1;
1.269 +
1.270 + do
1.271 + {
1.272 + const int c1 = events [mv_max + j]; /* positive */
1.273 + const int c2 = events [mv_max - j]; /* negative */
1.274 + const int c = c1 + c2;
1.275 + int a = j;
1.276 +
1.277 + sign_ct [0] += c1;
1.278 + sign_ct [1] += c2;
1.279 +
1.280 + if (a < mvnum_short)
1.281 + {
1.282 + is_short_ct [0] += c; /* Short vector */
1.283 + short_ct [a] += c; /* Magnitude distribution */
1.284 + }
1.285 + else
1.286 + {
1.287 + int k = mvlong_width - 1;
1.288 + is_short_ct [1] += c; /* Long vector */
1.289 +
1.290 + /* bit 3 not always encoded. */
1.291 + do
1.292 + bit_ct [k] [(a >> k) & 1] += c;
1.293 +
1.294 + while (--k >= 0);
1.295 + }
1.296 + }
1.297 + while (++j <= mv_max);
1.298 + }
1.299 +
1.300 + calc_prob(Pnew + mvpis_short, is_short_ct);
1.301 +
1.302 + calc_prob(Pnew + MVPsign, sign_ct);
1.303 +
1.304 + {
1.305 + vp8_prob p [mvnum_short - 1]; /* actually only need branch ct */
1.306 + int j = 0;
1.307 +
1.308 + vp8_tree_probs_from_distribution(
1.309 + 8, vp8_small_mvencodings, vp8_small_mvtree,
1.310 + p, short_bct, short_ct,
1.311 + 256, 1
1.312 + );
1.313 +
1.314 + do
1.315 + calc_prob(Pnew + MVPshort + j, short_bct[j]);
1.316 +
1.317 + while (++j < mvnum_short - 1);
1.318 + }
1.319 +
1.320 + {
1.321 + int j = 0;
1.322 +
1.323 + do
1.324 + calc_prob(Pnew + MVPbits + j, bit_ct[j]);
1.325 +
1.326 + while (++j < mvlong_width);
1.327 + }
1.328 +
1.329 + update(w, is_short_ct, Pcur + mvpis_short, Pnew[mvpis_short], *Pupdate++, updated);
1.330 +
1.331 + update(w, sign_ct, Pcur + MVPsign, Pnew[MVPsign], *Pupdate++, updated);
1.332 +
1.333 + {
1.334 + const vp8_prob *const new_p = Pnew + MVPshort;
1.335 + vp8_prob *const cur_p = Pcur + MVPshort;
1.336 +
1.337 + int j = 0;
1.338 +
1.339 + do
1.340 +
1.341 + update(w, short_bct[j], cur_p + j, new_p[j], *Pupdate++, updated);
1.342 +
1.343 + while (++j < mvnum_short - 1);
1.344 + }
1.345 +
1.346 + {
1.347 + const vp8_prob *const new_p = Pnew + MVPbits;
1.348 + vp8_prob *const cur_p = Pcur + MVPbits;
1.349 +
1.350 + int j = 0;
1.351 +
1.352 + do
1.353 +
1.354 + update(w, bit_ct[j], cur_p + j, new_p[j], *Pupdate++, updated);
1.355 +
1.356 + while (++j < mvlong_width);
1.357 + }
1.358 +}
1.359 +
1.360 +void vp8_write_mvprobs(VP8_COMP *cpi)
1.361 +{
1.362 + vp8_writer *const w = cpi->bc;
1.363 + MV_CONTEXT *mvc = cpi->common.fc.mvc;
1.364 + int flags[2] = {0, 0};
1.365 +#ifdef VP8_ENTROPY_STATS
1.366 + active_section = 4;
1.367 +#endif
1.368 + write_component_probs(
1.369 + w, &mvc[0], &vp8_default_mv_context[0], &vp8_mv_update_probs[0],
1.370 + cpi->mb.MVcount[0], 0, &flags[0]
1.371 + );
1.372 + write_component_probs(
1.373 + w, &mvc[1], &vp8_default_mv_context[1], &vp8_mv_update_probs[1],
1.374 + cpi->mb.MVcount[1], 1, &flags[1]
1.375 + );
1.376 +
1.377 + if (flags[0] || flags[1])
1.378 + vp8_build_component_cost_table(cpi->mb.mvcost, (const MV_CONTEXT *) cpi->common.fc.mvc, flags);
1.379 +
1.380 +#ifdef VP8_ENTROPY_STATS
1.381 + active_section = 5;
1.382 +#endif
1.383 +}
